Figure 7. Infection and infection-induced death of splenocytes from i.p.- or i.g.- infected C57BL/6N Wt and Ifnar1−/− mice.

Representative samples obtained 48 h after i.p. administration of 1×10∧6 CFU of strain LO28InlA* (upper panels) or i.g. administration of 5×10∧9 LO28InlA* (lower panels) to C57BL/6N Wt or Ifnar1−/− mice as indicated. Panels on the left were stained with anti-Lm antibody. Panels on the right were subjected to in situ TUNEL assay. Infected cells and TUNEL+ cells appear red. The orange background seen in the red pulp of some sections is caused by erythrocyte haemoglobin. The bar graphs show quantification of TUNEL+ cells from sections of four spleens of i.p-infected and six spleens of i.g-infected C57BL/6N (black bar) and Ifnar1−/− (grey bar) mice.